Transmission



June 9, 1936. H. A. KNOX ET AL 2,043,251

TRANSMISSION Filed Oct. 18, 1934 2 Sheets-Sheet l 28 Inventnrs Harry A-Knmx Thu-mas H-Nix.mn. 31y Attnrfle.

H. A. KNOX ET AL June 9, 1936.

TRANSMISSION Filed Oct. 18, 1954 2 Sheets-Sheet 2 Inv enturs Harry A-K1-L ax TH-Lamas H-N ixu'n Patented 9, 1936 f I UNITED STATES Pars'r OFFICE Harry L Knox, Davenport, Iowa, and Thomas Hay Nixon. Gettysburg. Pa.

Ami flfloli October 1a, 1934, semis. 14am 2 Claims. (01. 14-34:)

(Granted under the act of March 3, 1883, as amended April 39, 1928; 37 0. G. 757) The invention described herein may be manutive driving elements through the shift collars factured and used by or for the Government for It and 21 and the usual shift forks, not shown. governmental purposeawithout the payment t Journaled in the supports I and 1 of the .us of any royalty thereon. r casing is a first idler shaft 28 on which is mount- 5 The subject of this invention is a transmised a gear 24 meshing with the pinion It on the 5 sion, and it is intended more specifically as a drive shaft 8 and a gear 28 meshing with a gear transmission for heavy vehicles. 26 rotatable on a second idler shaft 21 jour- The main objects of the invention are the naled in the supports l and 1 of the casing I provision of a novel low speed and reverse gearand having rotatable thereon a second gear '28 10 ings and an efficient, economical and satisfacintegral with or secured to the gear 26. 1o tory transmission for heavy vehicles. 0n the driven shaft I8 is provided means for b With the foregoing and other objects in view. driving said shaft either through the gear 28, the invention resides in the novel arrangement when reverse drive is desired or through gear and combination of parts and in the details of 28 when a low speed is desired. While several construction hereinafter described and claimed, means may be employed to accomplish this result 15 it being understood that changes in the precise one simple form illustrated herein consists in embodiment of the invention herein disclosed feathering a gear 28 on the shaft it in position may be made within the scope of what is claimed to be selectively engaged with the gear 25 or without departing from the spirit of the inventhe gear 28. The gear 28 is provided with the tion. usual shift collar 88 adapted to be engaged bya 20 A practical embodiment of the invention is shift fork, not shown. illustrated in the accompanying drawings, If desired a clutch element It may be slidably wherein: a mounted on the driven shaft l8 to engage the Fig. 1 is a sectional view taken on the line element 82 and so drive the bevel. gear 33, and g i--l of Fig. 2. through it the control differential, not shown.

Fig. 2 is a sectional view taken on the lines A speedometer drive 34 may be provided on 2-2 of Fig. 1. the driven shaft as shown. Fig. 3 is a sectional view on the line 3-4 of In the modified form illustrated in Figs. 4, 5 Fig. 2. I and 6, the construction is the same as that here- Fig. 4 is a longitudinal section of a modified tofore described with the exception that the 80 formof the device. gears are in constant mesh and clutches are Fig. 5 is a transverse section. used to selectively lock the gears to the driven Fig. 6 is a section on the line 8-8 of Fig. 4. shaft. In this case we have the transmission Referring to the drawings by numerals of easing I, the bearing 8--8 for the drive shaft 8 5 reference: on which shaft are fast by splines It the gears 85 There is provided a transmission casing I hav- II and I2, and the shaft also has fast thereon ing a first support 1", a second support 1" and the gear I! and pinion ll. a third support 1. Journaled in the supports 1' Journaled in the transmission casing through and 1" by means of the bearings 8-8 is a drive bearing i8l8 is a driven shaft l8 parallel 40 shaft 8 which may be directly connected to the with the shaft 8. Loose on this shaft are gears 40 engine through a clutch as is usual. Secured on l1, l8, l8? and 28 in constant mesh with the the shaft 8 by the splinesll or in other suitrespective gears II, II, and I3 and with the able manner are gears II and I2, and also se= pinion ll. While these gears may-be mounted cured on the shaft. as herein shown integral loose on the shaft in any preferred manner, as therewith, is a gear l8 and pinion ll. herein shown, bushings 88, 38 and 81 are placed it Joumaled in the transmission casing through on the shaft and between these bushings and the bearings i8--l8 in the supports 1', I and I is respective gears, needle bearings '88 are intera driven shaft i8 parallel with the shaft 8. posed. Clutch elements 88-48 are provided for Mounted on this shaft are gears l1, l8, l8 and engagement with the clutch elements 48 on the 50 28 adapted to be selectively driven by the regears. These elements 88 are feathered on col- Mi spective gears H, I! and I8 and the pinion II to lars ll-ll which are keyed to the shaft l8, as impart to the driven shaft four desired speeds. seen most clearly at ll Fig. 6. As herein shown these gears l1, l8, l8 and 28 The idler shafts 28 and 21 are the same as are feathered on the shaft l8 andare thrown heretofore described and are provided wlththe into and out of engagement with their respecsame gears acting in the manner set forth in relation to Figs, 1, 2 and 3. The shaft II is provided with the gear 2! which may selectively engage gears 25 or 28 on the idler shafts.

In this instance the clutch Ii is omitted and the bevel gear is fast on the shaft i6.

While in one form of the device there has been shown and described shiftable gears and in the other form constant mesh gears with shiftable clutches, it is to be understood that any combination of the two falls within the spirit of this invention. For instance, the two high speed gears may be constant mesh gears with a shiftable clutch to selectively engage one .or the other while the lower speeds may be provided with shiftable gears.

The operation of the device is as follows:

The clutch ll being engaged, shifting the gear 2! to engage gear 2! will give reverse movement while engaging gear II with gear II will produce a low speed forward; shifting gear II into engagement with the pinion M will produce a low speed forward, while shifting gear i s into engagement with gear I! will produce an' intermediate speed'forward; shifting gear I l into engagement with gear I! will give a higher intermediate speed forward, while engaging I! with gear II will give high speed forward.

The same operations are performed and the same results obtained with the modified form, with the exception that the clutch I is absent.

We claim:

1. In a transmission, a first, second and third support, a drive shaft mounted in the first and second supports, a driven shaft mounted in all of the supports, change-speed gearing connecting the shafts and including low-speed gearing positioned adjacent the second support, first and second idler shafts mounted in the second and third supports, a gear on the first idler shaft meshing with the low speed gearing of the drive shaft, constantly meshed gears on the idler shafts, a second gear on the second idler shaft and fast to the meshed gear on said shaft, and a gear slidable on the driven shaft between the second and third supports and selectively engageable with the constantly meshed gear of the first idler shaft and the second gear on the second idler shaft.

2. A transmission embodying a drive shaft, is

driven shaft, change-speed gearing connecting 20 the shafts, a first idler shaft driven by the drive shaft, a second idler shaft, meshed gears on the first and second idler shafts, a second gear on the second idler shaft and fast to the meshed gear on said shaft, and a gear on the driven 25. 

